This chapter shall be known and may be cited as the "Borough
of Lansdale Stormwater Management Ordinance."
The Borough finds that:
A.
Inadequate management of accelerated stormwater runoff resulting
from development and redevelopment throughout a watershed can increase
flood flows and velocities, contribute to erosion and sedimentation,
overtax the carrying capacity of streams and storm sewers, greatly
increases the cost of public facilities to convey and manage stormwater,
undermine floodplain management and flood reduction efforts in upstream
and downstream communities, reduce groundwater recharge, and threaten
public health and safety.
B.
Inadequate planning and management of stormwater runoff resulting
from land development and redevelopment throughout a watershed can
also harm surface water resources by changing the natural hydrologic
patterns, accelerating stream flows (which increase scour and erosion
of streambeds and stream banks, thereby elevating sedimentation),
destroying aquatic habitat, and elevating aquatic pollutant concentrations
and loadings such as sediments, nutrients, heavy metals, and pathogens.
C.
A comprehensive program of stormwater management (SWM), including
reasonable regulation of development and activities causing accelerated
runoff, is fundamental to the public health, safety, welfare, and
the protection of the people of the Borough and all the people of
the Commonwealth, their resources, and the environment.
D.
Stormwater is an important water resource by providing groundwater
recharge for water supplies and base flow of streams, which also protects
and maintains surface water quality.
E.
Public education on the control of pollution from stormwater is an
essential component in successfully addressing stormwater.
F.
Federal and state regulations require certain municipalities to implement
a program of stormwater controls. The Borough is required to obtain
a permit for stormwater discharges from its separate storm sewer systems
under the National Pollutant Discharge Elimination System (NPDES).
The purpose of this chapter is to promote the public health, safety, and welfare within the Borough by maintaining the natural hydrologic regime and by minimizing the harms and maximizing the benefits described in § 338-2 of this chapter, through provisions designed to:
A.
Meet legal water quality requirements under state law, including
regulations at 25 Pa. Code § 93.1 et seq., to protect, maintain,
reclaim, and restore the existing and designated uses of the waters
of this Commonwealth.
B.
Minimize increases in stormwater volume and control peak flows.
C.
Minimize impervious surfaces.
D.
Provide review procedures and performance standards for stormwater
planning and management.
E.
Preserve the natural drainage systems as much as possible.
F.
Manage stormwater impacts close to the runoff source, requiring a
minimum of structures and relying on natural processes.
G.
Focus on infiltration of stormwater to maintain groundwater recharge,
to prevent degradation of surface water and groundwater quality, and
to otherwise protect water resources.
H.
Preserve and restore the flood-carrying capacity of streams.
I.
Prevent scour and erosion of stream banks and streambeds.
J.
Provide standards to meet National Pollution Discharge Elimination
System (NPDES) permit requirements.
K.
Address certain requirements of the Municipal Separate Stormwater
Sewer System (MS4) NPDES Phase II Stormwater Regulations.
L.
Provide for proper operation and maintenance of all stormwater management
facilities and best management practices (BMPs) that are implemented
in the Borough.
The Borough is empowered to regulate land use activities that
affect runoff, surface, and groundwater quality and quantity by the
authority of:
All regulated activities and all activities that may affect
stormwater runoff, including land development and earth disturbance
activity, are subject to regulation by this chapter. Regulated activities
include, but are not limited to:
A.
Land development;
B.
Subdivisions;
D.
Alteration of the natural hydrologic regime;
E.
Addition of new impervious or semi-pervious surfaces (i.e., driveways,
parking lots, roads, etc.); reconstruction of these existing surfaces
where there is no increase in impervious surface is not regulated;
F.
Construction of new buildings or additions to existing buildings;
G.
Redevelopment;
H.
Diversion piping or encroachments in any natural or man-made channel;
and
I.
Nonstructural and structural stormwater management best management
practices (BMPs) or appurtenances thereto.
A.
Regulated activities that create impervious surfaces smaller than or equal to 1,000 square feet do not have to apply the volume control requirements of this chapter. Regulated activities of this size are exempt from the peak rate control requirements and the SWM site plan preparation located in Article IV of this chapter. If the activity is found to be a significant contributor of pollution to the waters of this commonwealth, the Borough may enforce any of the above requirements.
B.
Regulated activities that create impervious surfaces greater than
1,000 square feet, up to and including 5,000 square feet, are exempt
only from the peak rate control requirements of this chapter. A small
project SWM site plan shall be required for small residential regulated
activities creating impervious surface greater than 1,000 square feet,
up to and including 5,000 square feet. Refer to Appendix I of this
chapter for an example of a small project SWM site plan.
Table 106.1 Impervious Surface Exemption Thresholds for
the Borough
| |||||
---|---|---|---|---|---|
Proposed Impervious Surface
| |||||
Chapter, Article or Section
|
Type of Project
|
0 to 1,000 square feet
|
>1,000 to 5,000 square feet
|
>5,000 square feet
| |
Article IV, SWM Site Plan Requirements
|
Development
|
Exempt
|
Not Exempt
|
Not Exempt
| |
§ 338-11, Volume Control Requirements
|
Development
|
Not Applicable
|
Not Exempt
|
Not Exempt
| |
§ 338-12, Peak Rate Control Requirements
|
Development
|
Exempt
|
Exempt
|
Not Exempt
| |
Erosion and Sediment Pollution Control Requirements
|
Must comply with Title 25, Chapter 102 of the Pennsylvania Code and any other applicable state, county, and municipal codes
|
C.
Agricultural activity is exempt from the peak rate control requirements and SWM site plan preparation requirements of this chapter, provided the activities are performed according to the requirements of 25 Pa. Code Chapter 102.
D.
Forest management and timber operations are exempt from the peak rate control requirements and SWM site plan preparation requirements of this chapter, provided the activities are performed according to the requirements of 25 Pa. Code Chapter 102.
E.
Any aspect of BMP maintenance to an existing SWM system made in accordance
with plans and specifications approved by the Borough is exempt.
F.
The use of land for gardening and/or landscaping for home consumption
is exempt from the requirements of this chapter.
H.
Additional exemption criteria:
(1)
Exemption responsibilities. An exemption shall not relieve the applicant
from implementing such measures as are necessary to protect public
health, safety, and property.
(2)
Drainage problems. Where drainage problems are documented or known
to exist downstream of or is expected from the proposed activity,
the Borough may deny exemptions.
(3)
Exemptions are limited to specific portions of this chapter.
(4)
HQ and EV streams. The Borough may deny exemptions in high-quality
(HQ) or exceptional value (EV) waters and source water protection
areas (SWPA).